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    <script>
        let arr =Array.of("张三",18,"男");
        console.log(arr);
        let obj = {
            0: "abc",
            1: "def",
            length: 2
        }
        console.log(obj);
        console.log(Array.from(obj));

        let a =[1,2,3,4,5,6,7,8];
        let b =a.find(function(item,idx,arr){return item>8})
        console.log(b);
        

        let c =a.findIndex(function(item,idx,arr){return item>8})
        console.log(c);
        
        let d =a.includes(9)
        console.log(d);
        
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